Check location argument

src/FaceRecognitionDotNet/FaceRecognition.cs

@@ -369,6 +369,7 @@ public static IEnumerable<double> FaceDistances(IEnumerable<FaceEncoding> faceEn
         /// <param name="model">The model of face detector to detect in image. If <paramref name="knownFaceLocation"/> is not null, this value is ignored.</param>
         /// <returns>An enumerable collection of face feature data corresponds to all faces in specified image.</returns>
         /// <exception cref="ArgumentNullException"><paramref name="image"/> is null.</exception>
+        /// <exception cref="InvalidOperationException"><paramref name="knownFaceLocation"/> contains no elements.</exception>
         /// <exception cref="ObjectDisposedException"><paramref name="image"/> or this object or custom face landmark detector is disposed.</exception>
         /// <exception cref="NotSupportedException"><see cref="PredictorModel.Custom"/> is not supported.</exception>
         public IEnumerable<FaceEncoding> FaceEncodings(Image image,
@@ -382,6 +383,9 @@ public IEnumerable<FaceEncoding> FaceEncodings(Image image,
             if (predictorModel == PredictorModel.Custom)
                 throw new NotSupportedException("FaceRecognitionDotNet.PredictorModel.Custom is not supported.");
 
+            if (knownFaceLocation != null && !knownFaceLocation.Any())
+                throw new InvalidOperationException($"{nameof(knownFaceLocation)} contains no elements.");
+
             image.ThrowIfDisposed();
             this.ThrowIfDisposed();
 
@@ -403,6 +407,7 @@ public IEnumerable<FaceEncoding> FaceEncodings(Image image,
         /// <param name="model">The model of face detector to detect in image. If <paramref name="faceLocations"/> is not null, this value is ignored.</param>
         /// <returns>An enumerable collection of dictionary of face parts locations (eyes, nose, etc).</returns>
         /// <exception cref="ArgumentNullException"><paramref name="faceImage"/> is null.</exception>
+        /// <exception cref="InvalidOperationException"><paramref name="faceLocations"/> contains no elements.</exception>
         /// <exception cref="ObjectDisposedException"><paramref name="faceImage"/> or this object or custom face landmark detector is disposed.</exception>
         /// <exception cref="NotSupportedException">The custom face landmark detector is not ready.</exception>
         public IEnumerable<IDictionary<FacePart, IEnumerable<FacePoint>>> FaceLandmark(Image faceImage,
@@ -413,6 +418,9 @@ public IEnumerable<IDictionary<FacePart, IEnumerable<FacePoint>>> FaceLandmark(I
             if (faceImage == null)
                 throw new ArgumentNullException(nameof(faceImage));
 
+            if (faceLocations != null && !faceLocations.Any())
+                throw new InvalidOperationException($"{nameof(faceLocations)} contains no elements.");
+
             faceImage.ThrowIfDisposed();
             this.ThrowIfDisposed();
 

test/FaceRecognitionDotNet.Tests/FaceRecognitionTest.cs

@@ -504,6 +504,27 @@ public void FaceEncodingsException()
             catch (ArgumentNullException)
             {
             }
+
+            try
+            {
+                var path = Path.Combine(ImageDirectory, TwoPersonFile);
+                if (!File.Exists(path))
+                {
+                    var binary = new HttpClient().GetByteArrayAsync($"{TwoPersonUrl}/{TwoPersonFile}").Result;
+
+                    Directory.CreateDirectory(ImageDirectory);
+                    File.WriteAllBytes(path, binary);
+                }
+
+                using (var image = FaceRecognition.LoadImageFile(path))
+                {
+                    var _ = this._FaceRecognition.FaceEncodings(image, new Location[0]).ToArray();
+                    Assert.True(false, $"{nameof(FaceRecognition.FaceEncodings)} must throw {typeof(InvalidOperationException)}.");
+                }
+            }
+            catch (InvalidOperationException)
+            {
+            }
         }
 
         [Fact]
@@ -533,6 +554,48 @@ public void FaceLandmarkException()
             catch (ArgumentNullException)
             {
             }
+
+            try
+            {
+                var path = Path.Combine(ImageDirectory, TwoPersonFile);
+                if (!File.Exists(path))
+                {
+                    var binary = new HttpClient().GetByteArrayAsync($"{TwoPersonUrl}/{TwoPersonFile}").Result;
+
+                    Directory.CreateDirectory(ImageDirectory);
+                    File.WriteAllBytes(path, binary);
+                }
+
+                using (var image = FaceRecognition.LoadImageFile(path))
+                {
+                    var _ = this._FaceRecognition.FaceLandmark(image, new Location[0]).ToArray();
+                    Assert.True(false, $"{nameof(FaceRecognition.FaceLandmark)} must throw {typeof(InvalidOperationException)}.");
+                }
+            }
+            catch (InvalidOperationException)
+            {
+            }
+        }
+
+        [Fact]
+        public void FaceLandmarkEmpty()
+        {
+            var path = Path.Combine(ImageDirectory, TwoPersonFile);
+            if (!File.Exists(path))
+            {
+                var binary = new HttpClient().GetByteArrayAsync($"{TwoPersonUrl}/{TwoPersonFile}").Result;
+
+                Directory.CreateDirectory(ImageDirectory);
+                File.WriteAllBytes(path, binary);
+            }
+
+            // empty image should return empty result
+            using(var bitmap = new Bitmap(640, 480, PixelFormat.Format24bppRgb))
+            using (var image = FaceRecognition.LoadImage(bitmap))
+            {
+                var landmarks = this._FaceRecognition.FaceLandmark(image).ToArray();
+                Assert.True(!landmarks.Any(), $"{nameof(FaceRecognition.FaceLandmark)} should return empty elements.");
+            }
         }
 
         [Fact]
@@ -2065,10 +2128,10 @@ private void FaceLocation(string testName, int numberOfTimesToUpsample, Model mo
             }
         }
 
-        private IEnumerable<FullObjectDetection> RawFaceLandmarks(Image img, IEnumerable<Location> faceLocations = null, PredictorModel model = PredictorModel.Large)
+        private IEnumerable<FullObjectDetection> RawFaceLandmarks(Image img, IEnumerable<Location> faceLocations = null, PredictorModel predictorModel = PredictorModel.Large)
         {
             var method = this._FaceRecognition.GetType().GetMethod("RawFaceLandmarks", BindingFlags.Instance | BindingFlags.NonPublic);
-            return method.Invoke(this._FaceRecognition, new object[] { img, faceLocations, model }) as IEnumerable<FullObjectDetection>;
+            return method.Invoke(this._FaceRecognition, new object[] { img, faceLocations, predictorModel, Model.Hog }) as IEnumerable<FullObjectDetection>;
         }
 
         private IEnumerable<MModRect> RawFaceLocations(Image img, int numberOfTimesToUpsample = 1, Model model = Model.Hog)